Isabella of Angoulême (; c.1188 – 4 June 1246) was queen consort of England as the second wife of King John from 1200 until John's death in 1216. She was also reigning Countess of Angoulême from 1202 until 1246.

Some of her contemporaries, as well as later writers, claim that Isabella formed a conspiracy against King Louis IX of France in 1241, after being publicly snubbed by his mother, Blanche of Castile for whom she had a deep-seated hatred. In 1244, after the plot had failed, Isabella was accused of attempting to poison the king. To avoid arrest, she sought refuge in Fontevraud Abbey where she died two years later, but none of this can be confirmed.